Investigating the presence of organophosphate esters in sediments from a typical fishing port agglomeration in Dalian, North China.

The presence of 14 organophosphate esters (OPEs) in surface sediments from a typical fishing port agglomeration in Dalian, North China was investigated for the first time. Tris(2-ethylhexyl) phosphate (TEHP), triphenylphosphine oxide (TPPO), and tris(2-chloroethyl) phosphate (TCEP) dominated 12 detectable OPEs (∑OPEs), with concentrations ranging widely from 0.56 to 352 ng/g (dry weight basis). The ∑OPE levels in sediments varied significantly across fishing harbors of various grades, and within the same grade, highlighting uneven distribution of OPE sources and inputs to harbors. The first- and second-class fishing harbors had higher geometric mean of ∑OPE contents compared to center and natural harbors, reflecting higher OPE pollution in these areas. Although there were significant correlations among the OPE congeners with high detection frequencies, the composition patterns of sediment OPEs varied considerably among fishing ports. The sediments in the center and first-class harbors had higher abundance of non-chlorinated OPEs (non-Cl-OPEs), suggesting heterogeneity in source strength and pollution characteristics of Cl- and non-Cl-OPEs in fishing ports. The distribution of OPEs in sediments was weakly associated with sediment organic carbon, but not socioeconomic variables, indicating complex controlling factors of their distributions in port sediments. The ecological risks of sediment OPEs were evaluated, and while OPE accumulations ranged broadly (7-684 ng/cm2), exposure hazards were negligible. The sediments in first- and second-class fishing harbors, which had greater OPE accumulation, were identified as reservoirs of OPEs in port aquatic environments.

Polycyclic aromatic hydrocarbons (PAHs) in seawater and sediments from the northern Liaodong Bay, China.

Levels, sources, and potential ecological risks of polycyclic aromatic hydrocarbons (PAHs) in surface seawater and sediments from the northern Liaodong Bay of China were seasonally investigated. Total concentrations of 16 PAHs varied from 145.96ng/L to 896.58ng/L in seawater, and from 191.99ng/g to 624.44ng/g in sediments. PAH concentrations in seawater differed significantly, whereas those in sediments exhibited a relatively stable pattern across seasons. PAHs with low molecular weight were predominant in seawater, but PAHs with high molecular weight were abundant in sediments. Crop straw and coal combustion were the main PAH pollution sources. The current levels of PAHs in the northern Liaodong Bay are relatively moderate compared with those in other bays and estuaries. Sediment from all sampling sites is characterized by low to medium ecotoxicological risk. No highly negative toxic effect could occur on the organisms and ecosystems in the northern Liaodong Bay.

Cloning and characterization of long-chain fatty alcohol oxidase LjFAO1 in lotus japonicus.

The Lotus japonicus EST database was searched against Arabidopsis thaliana AtFAO3, a full-length cDNA that encodes a membrane-bound, flavin-containing, hydrogen peroxide generating, long-chain fatty alcohol oxidase. One EST fragment was detected, and the corresponding full-length cDNA was obtained by screening a cDNA library of L. japonicus. The LjFAO1 genomic DNA was amplified by PCR, to give a product 3.6 kb in length. Comparison between the LjFAO1 cDNA and genomic DNA revealed that the LjFAO1 contains 3 exons and 2 introns. RT-PCR analysis showed that the LjFAO1 was expressed in the whole plant, with the highest expression level in the apex and the lowest expression level in the siliques. The LjFAO1 gene was down-regulated by cold stress in both the apex and the cotelydon of the 8-day old seedlings, the first time that a long-chain alcohol oxidase has been shown to respond directly to stress. The full length cDNA and a C-terminal truncated version were overexpressed in Escherichia coli. The full length version of LjFAO1 exhibited long-chain fatty alcohol oxidase activity and was subsequently purified by Ni-NTA chromatography. The active LjFAO1 protein showed substrate specificities toward 1-dodecanol, 1-hexadecanol, and 1,16-hexadecanediol with Km values 59.6 +/- 14.8 (microM), 40.9 +/- 8.2 (microM) and 19.4 +/- 1.5 (microM), respectively, suggesting apparent differences in substrate preferences with AtFAO3.